Joint connector block

ABSTRACT

A joint connector block, which easily meets a demand of a complicated and highly dense joint circuit, is provided. It includes: a block body  2  having a plurality of connector-fitting chambers  7  arranged in a line on one side of the block body and a busbar-receiving part  2   b  communicating with the connector-fitting chambers on an opposite side of the block body; a plurality of longitudinal busbars  3 , each of which includes at least one branch terminal  24  projecting in the connector-fitting chamber and at least one pair of clip terminals  23  situated on the side of the busbar-receiving part; and a plurality of lateral busbars  4 , each of which includes at least one branch terminal  26  projecting in the connector-fitting chamber and a connecting part  25  to be connected to the pair of the clip terminals  23  on the side of the busbar-receiving part, the lateral busbar being connected to the longitudinal busbar crossing the longitudinal busbar at right angles.

TECHNICAL FIELD

The present invention relates to a joint connector block which executesjoint-connection by crossing busbars extending in longitudinal andlateral directions.

BACKGROUND ART

FIG. 24 shows an example of a conventional joint connector block(referring to Japanese Utility Model Application Laid-Open No.H5-29230).

The joint connector block 51 includes: an upper casing 52 made ofsynthetic resin; lower casing 53 made of synthetic resin; and aplurality of busbars 54, each of which includes terminals and isarranged in a line in the lower casing 53. Each upward tab terminal 55of the corresponding busbar 54 projects in a corresponding connectorhousing 56 of the upper casing 52, thereby enabling a connector (outsideconnector) of an external wiring harness to be coupled with a connectorconsisting of the tab terminals 55 and the connector housing 56.

A plurality of the tab terminals 55 are arranged forming a line in thelongitudinal direction of the corresponding busbar 54. Each tab terminal55 projects in the corresponding connector housing 56, therebyjoint-connecting each outside connector to the connector consisting ofthe tab terminals 55 and the connector housing 56 through thecorresponding busbar 54. Thereby, electric power circuits or groundcircuits of the outside connector are electrically connected. The jointconnector block 51 is mounted on a motor vehicle and so on.

However, since the busbars 54 are arranged in a line forming a pluralityof lines in the conventional joint connecter block 51, the positions oftab terminals 55 for joint-connecting corresponding outside connectorsand positions of female terminals for joint-connection in thecorresponding outside connectors are limited, causing difficulty formeeting a demand of a complicated circuit structure and difficulty formeeting a demand of a different circuit form varying depending on typesof vehicle, and causing a problem that the joint connector block 51 mustbe designed and manufactured per a type of vehicle every time.

For example, Japanese Patent Application Laid-Open No. H7-147718proposes a busbar structure (not shown in a figure) of an electricjunction box, in which connectors are joint-connected with each other byarranging busbars in two directions, i.e. in the longitudinal andlateral directions. However, in this structure, when an outsideconnector is to be joint-connected, similarly to Japanese Utility ModelApplication Laid-Open No. H5-29230, only a tab terminal of a busbarextending in one direction is used to joint-connect the connector to theoutside connector, causing difficulty for meeting a demand of acomplicated and highly dense circuit form and difficulty for meeting ademand of a different circuit form which varies depending on types ofvehicle.

DISCLOSURE OF INVENTION

It is therefore an objective of the present invention to solve the aboveproblems and to provide a joint connector block, which can easily meet ademand of a complicated and highly dense joint circuit form or a demandof a different joint circuit form which varies depending on types ofvehicle.

In order to attain the above objective, a joint connector block of thepresent invention defined in claim 1 is a joint connector blockcomprising:

a block body having a plurality of connector-fitting chambers arrangedin a line on one side of the block body and a busbar-receiving partcommunicating with the connector-fitting chambers on an opposite side ofthe block body;

a plurality of longitudinal busbars, each of which includes at least onebranch terminal projecting in the connector-fitting chamber and at leastone pair of clip terminals situated on the side of the busbar-receivingpart; and

a plurality of lateral busbars, each of which includes at least onebranch terminal projecting in the connector-fitting chamber and aconnecting part to be connected to the pair of the clip terminals on theside of the busbar-receiving part, the lateral busbar being connected tothe longitudinal busbar crossing the longitudinal busbar at rightangles.

With the construction described above, the longitudinal busbars aremounted in the block body and thereafter the lateral busbars are mountedtherein, thereby the connecting part of the lateral busbar is insertedin and connected to the clip terminals of the longitudinal busbars.Thereby, the longitudinal and lateral busbars are connected to eachother. Each longitudinal or lateral busbar is mounted to a requiredposition in a required form. When each longitudinal or lateral busbar ismounted in the block body, each branch terminal of each busbar issimultaneously positioned projecting in the connector-fitting chamber.Each branch terminal of each busbar is arranged in a line in theconnector-fitting chamber. Each branch terminal is arranged in a matrixshape. Connectors of the outside wiring harness are inserted in theconnector-fitting chamber. The outside wiring harness (plurality ofelectric wires) is joint-connected by the branch terminals of thelongitudinal and lateral busbars.

A joint connector block of the present invention defined in claim 2 is,in the joint connector block as described in claim 1, characterized inthat the busbar-receiving part includes:

a plurality of slit grooves, each of which receives the longitudinalbusbar; and

a plurality of lateral slits, each of which engages with the connectingpart of the lateral busbar, the lateral slit crossing the slit groove atright angles.

With the construction described above, the longitudinal busbars areinserted in the slit groove and positioned, while the branch terminalsof the lateral busbars are inserted. The branch terminals of thelongitudinal and lateral busbars are arranged in a line. Each branchterminal is entered into the connector-fitting chamber through the slitgroove. The slit groove is positioned crossing the connector-fittingchamber at right angles. Each slit groove is formed between thepartition walls. The connecting part of the lateral busbar enters into ashallow lateral slit of the partition wall so as to be positionedwithout backlash and simultaneously the connecting part is clipped byand connected to the pair of the clip terminals of the longitudinalbusbar. The lateral slits are arranged in a line with the same pitch asthat of the connector-fitting chamber.

A joint connector block of the present invention defined in claim 3 is,in the joint connector block as described in claim 2, characterized inthat a concave groove is formed in a partition wall of theconnector-fitting chamber continuously from the lateral slit, the branchterminal of each said longitudinal or lateral busbar being insertedthrough the concave groove.

With the construction described above, Each branch terminal of thelongitudinal or lateral busbar is positioned in the concave groove ofthe partition wall which is adjacent to the slit groove and projects inthe connector-fitting chamber with an accurate pitch.

A joint connector block of the present invention defined in claim 4 is,in the joint connector block as described in any one of claims 1-3,characterized in that the branch terminal of the longitudinal busbar isoffset in a direction crossing at right angles from a connection partfrom which the pair of the clip terminals protrudes, while the branchterminal of the lateral busbar is on the same plane as that of theconnection part of the lateral busbar.

With the construction described above, the branch terminal of thelongitudinal busbar is offset in a direction crossing at right anglesand the branch terminal of the lateral busbar projects from the sameplane as that of the connection part of the lateral busbar so as to bearranged crossing the longitudinal busbar at right angles, thereby eachbranch terminal of the longitudinal or lateral busbar is arranged inparallel (in a line) and is arranged in a slit groove or in aconnector-fitting chamber being intermingled.

A joint connector block of the present invention defined in claim 5 is,in the joint connector block as described in any one of claims 1-4,characterized in that a plurality of ribs are projectingly formed on apartition wall of the connector-fitting chamber, the rib insulating thebranch terminals of each said longitudinal or lateral busbar from eachother.

With the construction described above, the branch terminals of each saidlongitudinal or lateral busbar are insulated from each other by the ribin the connector-fitting chamber and protected from an interference andso on.

A joint connector block of the present invention defined in claim 6 is,in the joint connector block as described in any one of claims 1-5,characterized in that each end of the pair of the clip terminalsprotrudes outward from the busbar-receiving part.

With the construction described above, the connecting part of thelateral busbar is easily inserted in and connected to the pair of theclip terminals of the longitudinal busbar, enabling visual observationfor confirming a connection between both busbars. A joint connectorblock of the present invention defined in claim 7 is, in the jointconnector block as described in any one of claims 1-6, characterized inthat a cover is fitted to the block body and each said longitudinal orlateral busbar abuts against the cover, thereby preventing each busbarfrom slipping out.

With the construction described above, the cover prevents each busbarfrom slipping out, thereby attaining no need to engage each busbar withthe block body.

A joint connector block of the present invention defined in claim 8 is,in the joint connector block as described in claim 7, characterized inthat the cover includes: a plurality of ribs against each of which anend of each said pair of the clip terminals abuts; and a plurality ofgrooves, each of which is formed between the ribs, the connection partof the lateral busbar entering in said groove.

With the construction described above, the end of the pair of the clipterminals of the longitudinal busbar abuts against an end face of therib and is positioned in the longitudinal direction of the terminalbeing prevented from slipping off. The end part of the connecting partof the lateral busbar engages with the groove between the ribs so as tobe positioned in a plate-thickness direction of the busbar, thereby theend of the connecting part abuts against the bottom of the groove sothat the lateral busbar is positioned in the longitudinal direction andprevented from slipping off.

A joint connector block of the present invention defined in claim 9 is,in the joint connector block as described in claim 8, characterized inthat said groove is provided with an inclined shaped guide surface onthe inlet side of the groove.

With the construction described above, the connecting part of thelateral busbar slides along the guide surface and enters into thegroove, thereby the connecting part is securely inserted into the grooveand the cover is securely mounted.

A joint connector block of the present invention defined in claim 10 is,in the joint connector block as described in any one of claims 1-9,characterized in that each said longitudinal or lateral busbar is formedby cutting a laterally linked terminal into a required shape.

With the construction described above, the laterally linked terminal iscut into a required shape (i.e. numbers or arrangement of each terminal,or length of the busbar) according to a specification of a circuit so asto easily make the longitudinal and lateral busbars required.

A joint connector block of the present invention defined in claim 11 is,in the joint connector block as described in claim 10, characterized inthat an unnecessary pair of the clip terminal or branch terminal is cutoff from the connecting part of the longitudinal or lateral busbar,and/or the connecting part is cut into a required length or cut at arequired position.

With the construction described above, by cutting off an unnecessarypair of the clip terminal of the longitudinal busbar, a connection withthe lateral busbar is partially cut. By cutting off an unnecessarybranch terminal of the longitudinal or lateral busbar, it becomespossible to meet a demand of a circuit of the outside wiring harness,said circuit including a part not to be connected. Further, for example,an unnecessary branch terminal of the longitudinal busbar is cut off,then the branch terminal of the lateral busbar is arranged on the cutportion, thereby enabling to meet a demand of a complicated jointcircuit.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded perspective view illustrating a preferredembodiment of a joint connector block according to the presentinvention.

FIG. 2 is a perspective view, which is almost a plan view, illustratinga state when each busbar is mounted on a block body.

FIG. 3 is a perspective view of a primary part illustrating a connectionstate of each busbar.

FIG. 4 is a perspective view illustrating a preferred embodiment of alongitudinal busbar (intermediate processed good).

FIG. 5 is a plan view illustrating a preferred embodiment of cuttingprocessing of a longitudinal busbar.

FIG. 6 is a plan view illustrating another preferred embodiment ofcutting processing of a longitudinal busbar.

FIG. 7 is a plan view illustrating a further preferred embodiment ofcutting processing of a longitudinal busbar.

FIG. 8 is a perspective view illustrating a preferred embodiment of alateral busbar (intermediate processed good).

FIG. 9 is a plan view illustrating a preferred embodiment of cuttingprocessing of a lateral busbar.

FIG. 10 is a plan view illustrating another preferred embodiment ofcutting processing of a lateral busbar.

FIG. 11 is a longitudinal sectional view illustrating a state when alower cover is mounted on a block body in which each busbar is received.

FIG. 12 is an exploded perspective view illustrating a preferredembodiment of a joint connector block according to the presentinvention.

FIG. 13 is an exploded perspective view illustrating a casing andbusbars with a terminal, which constitute a joint connector block.

FIG. 14 is a perspective view illustrating a state when connectors areinserted into a casing.

FIG. 15 is an exploded perspective view illustrating a preferredembodiment of a connector.

FIG. 16 is a perspective view illustrating another preferred embodimentof a joint connector block.

FIG. 17 is an exploded perspective view illustrating a preferredembodiment of an electric junction box according to the presentinvention.

FIG. 18 is a perspective view of the joint connector block shown in FIG.17.

FIG. 19 is an exploded perspective view of the joint connector shown inFIG. 17.

FIG. 20 is a side view of the joint connector shown in FIG. 19.

FIG. 21 is a perspective view illustrating a preferred embodiment of anelectric junction box according to the present invention.

FIG. 22 is a longitudinal sectional view of the joint connector blockshown in FIG. 21.

FIG. 23 is a perspective view of the joint connector shown in FIG. 21.

FIG. 24 is an exploded perspective view illustrating an example of aconventional joint connector block.

BEST MODE FOR CARRYING OUT THE INVENTION

In the following, the preferred embodiments of the present inventionwill be explained in detail with reference to the attached drawings.

FIG. 1 shows a preferred embodiment of a joint connector block accordingto the present invention.

The joint connector block 1 includes: a block body 2 (main cover orcasing) made of electrically insulating resin; a plurality oflongitudinal busbars 3 and a plurality of lateral busbars 4; and a lowercover 5 (cover) made of insulating resin for preventing each busbar 3, 4from coming off, wherein each busbar 3, 4 is made of electricallyconductive metal, includes at least one terminal, and is to be insertedin the block body 2 from the bottom. A plurality of outside connectors 6are inserted in the joint connector block 1 from the top.

The block body 2 includes connector-fitting parts 2 a situated at itsupper half and busbar-receiving parts 2 b situated at its lower half.The connector-fitting part 2 a includes a plurality of thin (long andnarrow) connector-fitting chambers 7 arranged in a line. Eachconnector-fitting chamber 7 is formed being partitioned by verticalpartition walls 10 with the same pitch in the inside of outer walls 8, 9situated in front and behind, and left and right. Each partition wall 10and the outer wall situated behind are projectingly provided with aplurality of ribs 11 with the same pitch. A space 7 (as a substitute useof the reference numeral) for receiving a terminal is formed between theadjacent ribs 11. The projection length of each rib 11 is short. Eachpartition wall 13 of a housing 12 made of insulating resin of theoutside connector 6 is positioned mating (facing) with the correspondingrib 11.

A female terminal (not shown in the figure) is engagingly received inbetween the adjacent partition walls 13 of the outside connector 6. Thefemale terminal is crimp-connected to an electric wire 14. The housing12 is formed in a thin shape with a wide board 12 (as a substitute useof the reference numeral) and a plurality of the partition walls 13arranged in the same pitch. The housing 12 and the female terminalsconstitute the outside connector 6. The wires 14 and the outsideconnectors 6 constitute a wiring harness. Each outside connector 6 isinserted in up to a face position flush with the upper end face of theblock body 2 (FIG. 1 illustrating an intermediate insertion state of theoutside connector 6) and fixed in a lump to the block body 2 with a longengaging member (not shown in the figure) made of synthetic resin. Areference numeral 15 indicates an engaging projection which engages withthe engaging member described above.

The block body 2 is integrally provided with a bracket 16 at its end inits longitudinal direction. The bracket 16 is clamped and fixed on avehicle body and so on by inserting a bolt through a hole 17 of thebracket 16.

As shown in FIGS. 2 and 3 (view from the bottom), in thebusbar-receiving part 2 b situated at the lower half of the block body2, there are provided a plurality of slit grooves 18 extending in thelongitudinal direction of the block body 2 arranged in a line with thesame pitch. A plurality of concave grooves 20, which is perpendicular toa plurality of vertical partition walls 19 that constitute the slitgrooves 18 and are arranged in a line, are formed being arranged in aline with the same pitch in the longitudinal direction of the block body2. Each concave groove 20 is arranged in a line in a direction crossingthe longitudinal direction of the block body 2 at right angles. Eachshort vertical lateral slit 21 is formed with the same pitch at thelower end of the corresponding concave groove 20. A plurality of theslit grooves 18 and a plurality of the lateral slits 21 (the concavegrooves 20) cross at right angles each other being positioned in amatrix shape. The lateral slit 21 communicates with the slit grooves 18situated left and right thereof in the crossing direction.

Each longitudinal busbar 3 including at least one terminal is arrangedin the slit groove 18, while each lateral busbar 4 including at leastone terminal is arranged along the lateral slit 21, and both busbars 3and 4 are positioned crossing at right angles (being connected) or beingindependent (separated) from each other.

As shown in FIG. 1, each longitudinal busbar 3 includes: a bandplate-shaped connecting part 22 that is a main body of the busbar 3; atleast one pair of clip terminals 23 (tuning fork-shaped terminal)projecting downward from the connecting part 22; and at least onepin-shaped terminal 24 (branch terminal) projecting upward with crossingthe connecting part 22 at right angles. Each lateral busbar 4 includes:a plate-shaped connecting part 25 that is a main body of the busbar 4;and at least one pin-shaped terminal 26 (branch terminal) projectingupward from the connecting part 25.

As shown in FIG. 4, the longitudinal busbar 3 is formed by stamping andbending one sheet of electrically conductive metal and thereafter, asshown in FIGS. 5-7, by cutting into a required shape.

As shown in FIG. 4, in the stamping and bending steps, formed is alaterally linked terminal 30 (intermediate processed good of thelongitudinal busbar) including: a first connecting part 22 extendingperpendicular to the horizontal direction; pairs of clip terminals 23standing up from the first connecting part 22 with the same pitch;vertical and thin linking part 27 extending in the extending directionof one clip piece 23 a of a pair of the clip terminals 23 from the firstconnecting part 22; pin-shaped terminals 24 continuing to and crossingone end of a little wide part 28 (second connecting part) on the baseside of the linking part 27; and a linked band 29 crossing the linkingpart 27 and continuing therefrom extending in the horizontal direction.

The pin-shaped terminal 24 is arranged on a position where the positionof a slot 31 situated between the pair of the clip terminals 23 isshifted in its longitudinal direction. Each clip terminal 23 has anarc-shaped contact 32 on the inner side of its end. A pair of thecontacts 32 is positioned having a small distance therebetween. The pairof the clip terminals 23 is known as itself. The second connecting part28 includes a part 28 a bent at right angles. The pin-shaped terminal 24is offset in a direction crossing at right angles from the connectingpart 22 by the bent part 28 a. The linking part 27 and the linked band29 are cut off in a later step. Holes 33 formed in the linked band 29are for perforation upon the processing.

Cutting processing (cutting of a portion indicated with inclined lines)shown in FIGS. 5-7 are carried out optionally according to a circuitform.

In an example of processing shown in FIG. 5, the linking part 27 and thelinked band 29 are integrally cut off from an end of the secondconnecting part 28. An unnecessary pin-shaped terminal 24, linking part27 and second connecting part 28 are cut off. An unnecessary pair of theclip terminals 23 is cut off from the base. The first connecting part 22is cut into a required length. Thereby, formed is a longitudinal busbar31 including: two pairs of the clip terminals 23 having no pairtherebetween on one side of the first connecting part 22; and twopin-shaped terminals 24 adjacent to each other on an opposite side ofthe first connecting part 22.

In an example of processing shown in FIG. 6, a middle pair of the clipterminals 23 is removed together with the first connecting part 22,thereby forming divided longitudinal busbars 32 and 33. One clip piece23 a of the middle pair of the clip terminals 23 is cut except the firstconnecting part 22, while another clip piece 23 b is cut off togetherwith the first connecting part 22.

In an example of processing shown in FIG. 7, a middle pair of the clipterminals 23 is removed together with the first and second connectingparts 22, 28 and a pin-shaped terminal 24, thereby forming dividedidentical longitudinal busbars 3 ₂. In FIGS. 6 and 7, another middlepair of the clip terminals 23 is also removed.

The processing of the longitudinal busbar 3 is not limited to theembodiments shown in FIGS. 5-7 and is carried out according to a circuitform.

FIGS. 8-10 show embodiments of the processing of the lateral busbar 4.

As shown in FIG. 8, formed is a laterally linked terminal 35(intermediate processed good of the lateral busbar) including: aplate-shaped connecting part 25 stamped from one sheet of electricallyconductive metal; a plurality of pin-shaped terminals 26 projecting froma plane of the connecting part 25 with the same pitch; and a linked band34 for connecting ends of the pin-shaped terminals 26.

The connecting part 25 is provided with holes 36 for perforation uponthe processing arranged with the same pitch. The hole 36 is not neededfor the joint-connection, therefore if the processing of the pin-shapedterminal 26 is possible, the hole 36 may be removed. The linked band 34is connected to an end of the pin-shaped terminal 26 through asmall-diameter notch 37 and is easily removed by bending.

In an example of processing shown in FIG. 9, a middle pin-shapedterminal 26 is cut from the connecting part 25, thereby forming alateral busbar 4 ₁ having no terminal at the middle. A pin-shapedterminal 26 situated at the end may be cut off (see reference numeral 42in FIG. 1). In each case, the corresponding terminal should be cut offfrom the base (root) thereof so as to leave the connecting part 25. Theconnecting part 25 acts as a contact (plate-shaped electric contact) tothe longitudinal busbar 3. The pin-shaped terminal 26 of the lateralbusbar 4 is formed longer than the pin-shaped terminal 24 of thelongitudinal busbar 3. The thickness, width, thickness-direction andwidth-direction are the same between the two pin-shaped terminals 24 and26.

In an example of processing shown in FIG. 10, the connection part 25 iscut at the middle so as to be divided into two short lateral busbars 4 ₂and 4 ₃. The processing of the lateral busbar 4 is not limited to theembodiments shown in FIGS. 9-10 and is carried out according to acircuit form.

These longitudinal and lateral busbars 3, 4 are connected to each othercrossing at right angles in the block body 2 as shown in FIGS. 1-3. Thereceiving process of the longitudinal busbars 3 and the insertionprocess of the lateral busbars 4 are carried out by reversing the blockbody. That is, as shown in FIG. 2, the longitudinal busbars 3 arereceived in the respective slit grooves 18 of the block body 2, and asshown in FIG. 3, the end of the pair of the clip terminals 23 ispositioned projecting outward from the slit groove 18.

As shown in FIG. 11, the pin-shaped terminal 24 of the longitudinalbusbar 3 is positioned projecting in the connector-fitting chamber 7situated in the upper half of the block body 2. Since the pin-shapedterminal 24 crosses the connecting part 22 at right angles (a littleprojecting in the direction of crossing at right angles), the pin-shapedterminal 24 passes through the concave groove 20 of the partition wall19 and projects in the connector-fitting chamber 7.

After the longitudinal busbars 3 are inserted, as shown in FIGS. 2-3,the lateral busbars 4 are inserted in the block body 2 simultaneouslybeing connecting to the longitudinal busbars 3 crossing the longitudinalbusbars 3 at right angles. That is, the pin-shaped terminal 26 (seeFIG. 1) of the lateral busbar 4 passes through the concave groove 20,which crosses the slit groove 18 (see FIG. 2) of the block body 2 atright angles, projects in the connector-fitting chamber 7 situated inthe upper half of the block body 2, and is positioned in parallel to thepin-shaped terminal 24 (see FIG. 1) of the longitudinal busbar 3. Eachpin-shaped terminal 24, 26 is isolated from each other by the rib 11 inthe connector-fitting chamber 7.

When the pin-shaped terminal 26 is inserted, simultaneously the baseside of the connecting part 25 (see FIG. 3) of the lateral busbar 4 isconnected to (clipped by) the pair of the clip terminals of thelongitudinal busbar 3. The base side of the connecting part 25 of thelateral busbar 4 is entered into the lateral slit 21 and positionedtightly, thereby securing the joint-connection between both busbars 3, 4without a positional shift. As shown in FIG. 3, the connecting part 25of the lateral busbar 4 is positioned projecting a little higher thanthe pair of the clip terminals 23 of the longitudinal busbar 3. The endsof the pin-shaped terminals 24, 26 (see FIG. 1) are positioned at thesame height.

After both busbars 3, 4 are mounted in the block body 2, as shown inFIG. 11, the lower cover 5 is mounted on the block body 2, therebypreventing each busbar 3, 4 from slipping off.

As shown in FIGS. 1 and 11, the lower cover 5 includes a plurality ofgrooves 38 arranged in a line with the same pitch in the arrangementdirection of the connector-fitting chambers. Each groove 38 isconstituted with pairs of ribs 39 on both sides thereof. An end of theconnecting part 25 of the lateral busbar 4 is inserted in the groove 38.The end of the connecting part 25 abuts against a bottom face 38 a ofthe groove 38 and is supported there. The end of the pair of the clipterminals 23 of the longitudinal busbar 3 abuts against an end face 39 aof the rib 39 and is supported there. A taper-shaped guide face 39 b isformed on the entrance side of the groove 38. The connecting part 25 ofthe lateral busbar 4 is smoothly inserted along the guide face 39 b. Theconnecting part 25, which is a connecting portion of the lateral busbar4, is accurately positioned with the groove 38, thereby securing thecontact with the pair of the clip terminals 23.

The pitch of each groove 38 is the same as the pitch of eachconnector-fitting chamber and the pitch of each lateral slit 21 (thepitch of each concave groove 20). The pitch of each rib 39 is the sameas the pitch of each slit groove 18. The projecting length of theconnecting part 25 from the end of the pair of the clip terminals 23 isthe same as the depth of the groove 38.

As shown in FIGS. 1 and 11, the lower cover 5 includes walls 40-42located in front and behind, and left and right, and at the bottom. Thegrooves 38 and ribs 39 are formed on the inner side of the wall 42located at the bottom. Each wall 41 situated left or right of the lowercover 5 is provided with a flexible engaging concave 44 which engageswith a engaging projection 42 of the block body 2.

As shown in FIG. 11, when the lower cover 5 is engaged with the blockbody 2, the bottom surface 42 (as a substitute use of the referencenumeral) is approximately flush with a bottom surface 16 a of thebracket 16 of the block body 2 (flush with the same plane or situated alittle higher than the bottom surface 16 a of the bracket 16). Thereby,the joint connector block 1 can be mounted on a mount of a vehicle bodyand so on compactly without interference. Further, the package densityupon transportation can be reduced.

Of course the directional characteristic of the joint connector block 1may be changed into various directions depending on its mountingdirection to a vehicle body and so on. Of course the longitudinal busbar3 and the lateral busbar 4 may be reversed depending on the mountingdirection of the joint connector block 1.

In the following, a joint connector block and its assembling method willbe explained, by which an engaging member for fixing a plurality ofconnectors can be mounted with a good workability, a secureconnector-fixing force can be obtained, a good reliability ofconnector-fixing can be obtained, the mounting of the engaging membercan be confirmed easily securely by visual observation, and anincomplete insertion of a connector can be securely prevented fromoccurring.

FIG. 12 shows a preferred embodiment of a joint connector blockaccording to the present invention.

The joint connector block 101 includes: a casing 102 (block body) madeof synthetic resin; a plurality of connectors 103 received in the upperhalf of the casing 102 being arranged in a line; a pair of spacer pins104 made of synthetic resin as an engaging member for pushing and fixingan upper ends of the respective connectors 103 onto an upper ends of thecasing 102 situated on both sides of the casing 102; a plurality oflongitudinal and lateral busbars 105, 106 (see FIG. 13) having aterminal, which are received in the lower half of the casing 102; and alower cover 107 made of synthetic resin, which engages with the bottomof the casing 102.

Each spacer pin 104 is arranged on the upper end of the casing 102 atboth sides in the width direction (left and right) and fixed on thecasing 102 by the respective engaging members. That is, the spacer pin104 includes: a plate-shaped vertical wall 108 extending in thelongitudinal direction of the spacer pin 104; a horizontal wall 109 onthe upper side crossing the wall 108 at right angles; vertical engagingwalls 110 continuing to and crossing each wall 108, 109 at the front andrear ends thereof; and convex part 112 including inwardly extendingengaging part 111 at the center of the vertical wall 108. The wall 108functions as a part extending along the wall 118 of the casing 102,while the wall 109 functions as a part abutting against the connector103. The convex part 112 functions as a protection wall.

The engaging wall 110 includes an inwardly extending engaging projection113 and has flexibility in the thickness direction with a vertical slit114 formed between the vertical wall 108 and the engaging wall 110. Thereference numeral 115 denotes a hole for the engaging projection 113.

The convex part 112 (protection wall) is formed in a shape with narrowwalls 112 a situated in front and behind and wide wall 112 b situated atthe front side thereof, and includes the engaging part 111 at innerlower end and an opening (the hole) at the upper end. The engaging part111 has a horizontal engaging face extending upward. The narrow wall 112a continues to the vertical wall 108 by way of a slit 163 and isprovided with flexibility in the thickness direction with the slit 163at the convex part 112.

An inner surface of the wall 109 is formed flat and the inner surfaceabuts against an upper end of each connector 103, thereby preventing theconnector 103 from slipping off. A vertical rib 116 stands up from thecenter in the width direction of an outer surface of the wall 109. Therib 116 is reinforced by a small lateral rib 117, thereby preventing thewall from bending and keeping the flatness of the inner surface of thewall.

As shown in FIG. 13, the casing 102 is provided with an engagingprojection 119 for engaging with the engaging projection 111 of thespacer pin 104 (see FIG. 12) at the center on the outer surface of thewalls 118 situated on both sides right and left. The casing is alsoprovided with an engaging projection 121 for engaging with the engagingprojection 113 of the engaging wall 110 (i.e. engaging arm) of thespacer pin 104 at both ends situated right and left of walls 120situated on both sides in front and behind. Each engaging projection119, 121 has an inclined face extending upward. The outside of theengaging projection 121 situated in front and behind is surrounded by aprotection wall 122 that is integral with the casing 112. A gap 123 forreceiving the vertical wall 108 of the spacer pin 104 (see FIG. 12) isprovided between an outer wall 122 a of the protection wall 122 and thewall 118. The engaging wall 110 of the spacer pin 104 enters into arectangular inside space 124 of the protection wall 122.

As shown in FIG. 12, the engaging wall 110 of the spacer pin 104 issurrounded by the protection wall 122 so as to being protected frominterference with the outside. An engaging state between the engagingprojection 111 and the engaging projection 119 of the casing 102 (seeFIG. 13) is protected by being surrounded by the convex part 112 andprotected from interference with the outside. Thereby, the engagingstate of the spacer pin 104, that is, the fixing state of each connector103 (see FIG. 12) is secured stably, preventing the spacer pin 104 fromslipping off. When the casing 102 is short (for example, half the lengthof the casing shown in FIG. 12), of course the spacer pin 104 alsobecomes short, then the engaging means 111, 119 become unnecessary. Thespacer pins 104 situated right and left are identical to each other,thereby reducing the cost of a mold for molding.

As shown in FIG. 13, a plurality of connector-fitting chambers 125 arearranged in a line in the upper half of the casing 102. Theconnector-fitting chambers 125 are partitioned by partition walls 126.The partition wall 126 is provided with a rib 128 corresponding to apartition wall 127 (see FIG. 14) of a connector-fitting chamber of theconnector 103. The rib 128 isolates branch terminals 129, 130 of busbars105, 106 from each other.

At each end left and right of an opening of each connector-fittingchamber 125, there is provided a small rectangular notch (hollow) 131 onthe wall 118 of the casing 102. As shown in FIG. 14, corresponding toeach notch 131, there is provided a lateral rectangular horizontalprojection 133 at each end left and right of the upper end of a housing132 made of synthetic resin of the connector 103. The height of theprojection 133 is equal to the depth of the notch 131 and the projectinglength of the projection 133 is equal to the width of the notch 131,i.e. the thickness of the wall 118.

When the projection 133 abuts against the horizontal wall 109 located onthe upper side of the spacer pin 104 (see FIG. 12), the connector 103 isprevented from slipping off. The spacer pin 104 does not abut againstany part of the housing except the projection 133. A plurality of theconnector-fitting chambers located from the left end to the right end ofthe connector 103 function effectively without being closed by thespacer pin 103. When the projection 133 enters into the notch 131, theupper end of the casing 102 is flush with the upper end of the connector103, thereby preventing the connector 103 from projecting upward.

As shown in FIG. 15, the connector 103 includes the housing 132 made ofsynthetic resin and small female terminals 134 having an electric wire,which are received in a line in the housing, thereby the connector 103is formed thin. The housing 132 includes a wide plate-shaped base wall135 and a plurality of partition walls 127 standing up from the basewall 135 with the same pitch. An opening end of the partition wall 127is provided with a flexible engaging piece 136 for engaging with theterminal 134. The base wall 135 is provided with a engaging projection139 for engaging with a hole 138 of the terminal 134 in eachterminal-receiving chamber 137 between the partition walls. The terminal134 is fixed in the thickness direction of the connector 103 by theengaging piece 136 and fixed in the longitudinal direction of theterminal-receiving chamber 137 by the engaging projection 139.

The outwardly extending projection 133 is formed at the upper end ofboth side walls 140 of the housing 132. The lower end of the side wall140 is provided with a projecting plate 141, which is a stabilizer forpreventing falling down. The connector 103 is not formed as a kit-cuttype (i.e. a plurality of the housing being connected in a line so as tobe cut) but a type of being molded independently. The terminal 134includes a female electric contact 142 on one side thereof and awire-connecting part 143 on the opposite side thereof. There is provideda resilient contact piece for the branch terminals 129, 130 of thebusbars 105, 106 (see FIG. 13).

As shown in FIG. 13, the busbars 105, 106 are arranged crossing eachother at right angles extending longitudinally and laterally,respectively, connecting to each other by a pair of clip terminals 144and a connecting part 145, respectively. Each busbar 105, 106 includes apin-shaped branch terminal 129, 130 situated on the reverse side of thepair of the clip terminals 144 and the connecting part 145. The casing102 includes slits and grooves (not shown) arranged with the same pitchfor receiving the longitudinal busbar 105 and each branch terminal 129,130 in the lower half of the casing. The lower cover 107 (see FIG. 12)is mounted on the casing 102 when each busbar 105, 106 is received inthe casing 102, and the lower cover 107 is fixed by an engagingprojection 147 (see FIG. 13).

As shown in FIG. 14, the connector 103 is inserted into the casing 102and each branch terminal 129, 130 is inserted into the correspondingfemale terminal 134 (see FIG. 15) so that each connector 103 isjoint-connected to each other through the busbar 105, 106. Each electricwire 148 (see FIG. 12) guided out from the connector constitutes awiring harness 149.

The connector 103 is inserted in the casing one by one, and after itsheight is checked, the spacer pin 104 is mounted. The connector may beinserted into the casing one by one by using a jig, which is connectedto an actuator such as an air cylinder, in an automatic assembly step.

In such a case, a sensor (not shown) may detect the stroke of thecylinder every time the connector 103 is inserted, or alternatively, asensor may detect the position of the upper end of the housing of theconnector 103, thereby the insertion height of the connector 103 can becontrolled.

Although FIG. 14 illustrates a state when a plurality of the connectors103 are halfway inserted for convenience, actually as described above,preferably, each connector 103 is completely inserted one by one. Asshown in FIG. 14, a plurality of the connectors 103 may besimultaneously inserted with the jig so as to control the height. Suchconstructions are effective as a method of assembling a joint connectorblock.

In the event that the connector 103 is incompletely inserted withoutcarrying out the height control, since the spacer pin 104 interfereswith the highly projecting incompletely inserted connector 103 causingthat the spacer pin 104 cannot be mounted on the casing 102, therefore aworker can detect the abnormality easily. In the event that theconnector 103 is incompletely inserted, by pushing strongly downward thespacer pins 104 situated left and right simultaneously, the incompletelyinserted connector 103 can be inserted completely, thereby securelypreventing the abnormality from occurring.

FIG. 16 is a perspective view illustrating another preferred embodimentof a joint connector block according to the present invention.

The joint connector block 151 includes: a casing 152 made of syntheticresin; a lower cover 153; a plurality of connectors (not shown) to bereceived in a line in the upper half of the casing 152; and a pair ofspacer pins 154 to be slidably mounted in the longitudinal direction ofthe casing 152 at the upper end on both sides left and right of thecasing 152.

The spacer pin 154 includes a rectangular pole-shaped body 155 and apair of flexible short locking arm 157, which is provided protrudinglyfrom a wide base end 156 of the body 155 in parallel with the body 155.The top and bottom surfaces of the body 155 are provided with therespective grooves extending in the longitudinal direction thereof so asto prevent the bend from occurring. Each locking arm 157 is providedwith an inwardly extending locking projection 157 a at an end thereof.

The casing 152 is integrally provided with frame-shaped guides 160 forreceiving the spacer pin at the upper end of walls 159 situated left andright. The middle guide 160 integrally continues to the upper end of apartition wall 162 of a connector-fitting chamber 161. The lockingprojection 157 a engages with the guide 160. The spacer pin 154 isinserted when all of the connectors are inserted in the casing 152. Theend of the spacer pin 154 abuts against the partition wall 162 and ishalted.

The housing of the connector may includes a projection (see FIG. 14),which is abutted by the spacer pin, at the upper end thereof.Alternatively, the spacer pin 154 may directly abut against the upperend of the housing (preferably, the upper end face of the wall on theshort side of the housing), which is cut into a required length beingseparated from a chain-shaped housing member. In this case, the spacerpin 154 can abut against the housing with a wide area, thereby securelypreventing the connector from slipping out and simplifying a mold formolding the housing.

The spacer pins 154 are identical left and right, and can be commonlyused. Preferably, the insertion height may be controlled as describedabove and thereafter the spacer pin 154 may be inserted. In the eventthat an incomplete insertion of the connector takes place, an end 155 aof the spacer pin 154 abuts against the incompletely inserted connector,thereby detecting the abnormality.

In each preferred embodiment as described above, the electric wire 148may be connected to the terminal of the connector 103 not by crimpingbut by pressure-welding. If the thickness of the wall 118 of the casing102 is large, the notch 131 may be a concave groove which does notpenetrate through the wall 118. Normally, a pair of the spacer pins 104,154 is used, however instead, if the width of the connector 103 issmall, only one spacer pin 104, 154 may be arranged on one side of theconnector 103. The projection 133 of the connector 103 may have not arectangular shape but a cylindrical shape. The shapes of the projection133 and the notch 131 of the casing 102 may have a shape for matching(for example, when the projection 133 having a cylindrical shape, thenotch having a half-circle shape) besides the rectangular shape. Eachdirection of front and behind, left and right or upper and lower isdefined depending on the mounting direction of the joint connector blockonto a vehicle body or the like, therefore each direction of front andbehind, left and right or upper and lower may be reversed depending onthe mounting direction.

In the following, an electric junction box will be explained, by whichconnectors can be smoothly coupled with each other, an undesirableinterference between terminals can be prevented from occurring, andreliability of the terminal connection can be maintained and improved.

FIG. 17 shows a preferred embodiment of an electric junction boxaccording to the present invention.

A joint box (electric junction box) to be mounted on a vehicle such as amotor vehicle is an electrically connecting component, in which an outercircuit is connected to a circuit structure of busbars and so on forconstituting a joint circuit through a wiring harness so as to make anelectric signal diverge to plural signals.

The joint box 210 (electric junction box) includes a joint connectorblock 212 and joint connectors 225. The joint connector block 212includes a casing 213 made of insulating resin, a plurality oflongitudinal busbars 243 and a plurality of lateral busbars 244, both ofwhich are inserted into the casing 213 from the bottom, and a cover (notshown) made of insulating resin for preventing each busbar 243, 244 fromcoming off. Each joint connector 225, which is connected to electricwires 241, is inserted into the casing 213 from the top. Each femaleterminal 233, which is received in a housing 226, is connected to acorresponding tab terminal 243 a, 244 a of the busbar 243, 244,respectively.

The joint box 210 of the present invention positions the joint connector225, which is received into a corresponding connector-fitting chamber218, and prevents an undesirable interference between the tab terminal243 a, 244 a and the female terminal 233 from occurring, therebyimproving the reliability of terminal connection. The joint box 210includes: the casing 213 which has connector-fitting part 217 that has aplurality of connector-fitting chambers 218 on the upper side and abusbar-receiving part 219 for receiving the busbars 243, 244 on thelower side; the housing 226 for receiving the female terminals 233; andthe joint connectors 225, each of which fits into the correspondingconnector-fitting part 217. Each guide groove 223 is formed in both sidewalls 214 a which constitutes a connector-fitting chamber 218. Eachguide rib 224 (see FIGS. 19 and 20) for engaging with the correspondingguide groove 223 is formed on both side walls 231 on the insertion endof the housing 226.

Instead, the guide rib may be formed on both side walls 214 a of theconnector-fitting chamber 218 and the guide groove may be formed in bothside walls 231 of the housing 226.

Since the guide rib 224 is formed is formed on both side walls 231 onthe insertion end of the housing 226, the electric contact 234-side ofthe female terminal 233, which is mounted in the joint connector 225, isbound, thereby effectively preventing the positional displacement in adirection crossing the insertion direction of the joint connector 225 atright angles from occurring.

In the following a primary constitutional part and its functional actionof the joint box 210 will be explained in detail.

The casing 213 includes: the connector-fitting part 217 in its upperhalf; the busbar-receiving part 219 to be covered with the cover (notshown) in its lower half; and a pair of brackets 220 to be fixed on apanel (not shown) of a vehicle body or the like in the front and reardirection.

The connector-fitting part 217 includes a plurality of the slot-shapedconnector-fitting chambers 218 arranged in a line, each chamber 218being divided by vertical partition walls 218 a with the same pitch in aframe surrounded the walls situated front and rear, and left and right.A plurality of the ribs 218 b are formed on the partition wall 218 a andthe rear wall 214 b with the same pitch and a space for receiving aterminal is formed between the respective ribs 218. The projectionlength of the rib 218 is small and each partition wall 229 of thehousing 226 of the joint connector 225 is positioned facing thecorresponding rib 218 b.

Each connector-fitting chamber 218 is formed open on its upper part. Itseach narrow wall situated left and right is the corresponding side wall214 a situated left and right facing each other of the casing 213. Eachwide wall situated in front and rear is the partition wall 218 a, frontwall 214 c or rear wall 214 b.

The guide groove 223 is formed in the side wall 214 a situated left andright of the connector-fitting chamber 218. The guide groove 223 isformed communicating with the bottom part from an end of the opening ofthe connector-fitting chamber 218 (see FIG. 18). Therefore, the jointconnector 225 is slidably guided thoroughly, thereby improving theworkability of fitting of the joint connector 225.

The guide rib 224 is formed projecting in the standing-up direction ofthe partition wall 229 on both side walls 231 of the joint connector 225(housing 226) corresponding to the guide groove 223 (see FIGS. 19 and20). The guide rib 224 engages with the guide groove 223, therebypreventing an undesirable interference between the terminals fromoccurring and improving the reliability of the terminal connection.

A rectangular concave part 245 is formed at the end of the opening ofthe side walls 214 a situated left and right of the connector-fittingchamber 218. A projection 246 is formed projecting in a lateraldirection (left and right direction) on both side walls 231 of the jointconnector 225 (housing 226) corresponding to the concave part 245 (seeFIGS. 19 and 20).

The projection 246 is formed on the end of the opening from which theelectric wires 241 are guided out from the joint connector 225. An endface of the projection 246 is formed flush with an end face of thehousing 226. Thereby, the back face (flat face) of a connection part ofthe engaging spacer 237 is put to the end faces of the projection 246and housing 226, thereby stabilizing the fixed position of the engagingspacer 237 and securely engaging the joint connector 225 withoutlooseness.

The cover (not shown) prevents the busbars 243, 244 from coming off bybeing put to the busbar-receiving part 219 from the bottom after thebusbars 243, 244 are mounted in the busbar-receiving part 219. A lockingprojection (not shown) is formed on both side walls 214 a of the casing213 and a locking part (not shown) is formed on an inner face of thecover, thereby the locking projection engages with the locking part soas to mount the cover when the cover is applied onto the casing 213.

The busbar-receiving part 219 is formed inside the casing andconstituted by longitudinal grooves (not shown) partitioned by aplurality of partition walls (not shown) extending in the front and reardirection and lateral grooves (not shown), each of which communicatesnotches formed on the partitioned walls with each other in a directioncrossing the longitudinal groove at right angles.

Each busbar 243, 244 is formed by stamping an electrically conductiveplate and being bent according to needs. The longitudinal busbar 243includes a band part 243 b, a plurality of pairs of clip terminals 243 cformed on one side of the band part 243 b, and tab terminals 243 aformed on the opposite side of the band part 243 b. Each pair of theclip terminals 243 c has a slit 243 d between both terminals. The slit243 d clips a band part 244 b of the lateral busbar 244 so as toconstruct the joint circuit.

The lateral busbar 244 includes a band part 244 b and at least one tabterminal 244 a formed on one side of the band part 244 b. The tabterminal 244 a penetrates through a terminal insertion hole formed inthe bottom part (not shown) of the busbar-receiving part 235, projectsinto the connector-fitting chamber 218, and is connected to the femaleterminal 233 of the joint connector 225.

A frame 216 for receiving an arm 239 of the engaging spacer 237 isformed outside the connector-fitting part 217 at a corner of an outerwall of the joint connector block 212. The arm 239 is inserted into acylinder of the frame 216, thereby the arm 239 is protected by the frame216, preventing the arm 239 from abruptly coming out by an interferencewith the outside.

The long engaging spacer 237 made of insulating resin includes aconnection part 238 extending straightly in the horizontal direction, apair of arms 239 continuing to both ends of the connection part 238crossing at right angles, and a vertical depending wall 240 continuingto one side of the connection part 238 crossing at right angles. A slit240 a is formed at a crossing line between the arm 239 and the verticaldepending wall 240, allowing the arm to be bent. The back face of theconnection part 238 is formed flat so as to be put to the end of aplurality of the joint connectors.

A locking claw 239 a projecting inward is formed on an inner face on theend side of the arm 239. When the engaging spacer 239 faces the sidewall 214 a of the casing 213 and is applied onto the upper end of theside wall 214 a, the arm 239 is inserted into the cylinder of the frame216 and the locking claw 239 a engages with the projection 216 a in thecylinder, thereby engaging the engaging spacer 237. Thereby, theconnection part 238 is put to a plurality of the ends of the jointconnectors 225 and a plurality of the joint connectors 225 iscollectively engaged, thereby securely fixing the joint connectors 225.

As shown in FIGS. 19 and 20, the joint connector 225 includes femaleterminals 233 to be connected to the tab terminals 243 a, 244 a of thebusbars 243, 244 (see FIG. 17) and the plate-shaped housing 226. Thejoint connector 225 and the electric wires 241 to be connected to thefemale terminals 233 constitute a wiring harness.

The housing 226 made of insulating resin includes a flat board 227,partition walls 229 and front walls 228 standing up crossing at rightangles from the board 227, and side walls 231 at both sides. Aprojection 229 a for preventing the female terminal 233 from coming outis formed at the middle of the partition wall 229. The projection lengthof the projection 229 a is formed so as not to obstruct the insertion ofthe female terminal 233 which is inserted from the top.

A thin and long terminal-receiving part 230 is formed between theadjacent partition walls 229 of the housing 226 so as to receive thefemale terminal 233 form a direction indicated by an arrow in FIG. 19.The electric contact 234 of the received terminal 233 abuts against thefront wall 228 of the housing 226 so as not to come off in the forwarddirection, while the electric contact 234 abuts against the projection229 a so as not to come off in the upward and backward directions. Thatis, the female terminal 233 received in the terminal-receiving part 230does not come off from the terminal-receiving part 230.

Insertion holes 228 a for inserting the tab terminals 243 a, 244 a ofthe longitudinal and lateral busbars 243, 244 are formed in the frontwalls 228 of the housing 226. The inlet of the hole 228 a is formed on atapered surface 228 b, thereby each tab terminal 243 a, 244 a is guidedby the tapered surface 228 a so as to be inserted into the electriccontact 234, and clipped by a resilient force of a resilient contactpiece 234 a.

The side wall 231 is formed parallel to the partition wall 229. Theterminal-receiving part 230 is also formed between the side wall 231 andthe partition wall 229. Outside the side wall 231, there are formed athick part 231 b extending toward the front wall 228 along the side wall231 and thick part 231 a extending toward the opposite side (electricwire-guiding-out side) along the side wall 231. The side wall 231 isreinforced by these thick parts 231 a, 231 b, thereby preventing theside wall 231 from falling down.

A projection 246 for engaging with a concave part 245 formed in the sidewalls 214 a situated left and right of the connector-fitting chamber 218is formed on the rear end side of the one thick part 231 a. With themutual action between the projections 245 and 246, the rear end side ofthe joint connector 225 is positioned.

A guide rib 224 formed in L-shape in its cross section is formed on theend side of the opposite thick part 231 b. The guide rib 224 includes aside end 247 and front end 248. The side end 247 projects toward thestanding-up direction of the side wall 231, extending along the sidewall 231. The front end 248 is a thick part and continues to the endside of the side end 247 crossing at right angles.

The projecting length h1 (see FIG. 20) of the side end 247 is formed tobe approximately half of the height h2 of the partition wall 229 or theside wall 231, which partitions the terminal-receiving part 230, therebypreventing the side end 247 from being deformed and securing thepositioning of the joint connector 225.

The length of the side end 247 is formed half of the length of theelectric contact 234 of the female terminal 233, thereby restricting theguide rib 224 with the guide groove 223 and preventing the looseness ofthe joint connector 225 from occurring.

The rear end face 247 b of the side end 247 is slightly inclinedrelatively to the side wall 231, thereby preventing an undesirableinterference from occurring when the joint connector 225 is taken outfrom the connector-fitting chamber 218.

The front end 248 is formed thick and the thick part is protrudedinwardly. Since the thickness of the front end 248 is formedapproximately the same as the width W (see FIG. 18) of the guide groove223, the inner end face 248 b and the side end face 247 c abut againstwall faces 223 a in the groove situated at both sides of the guidegroove 223 so that the joint connector 225 is positioned in the left andright direction.

The front end face 248 a of the front end 248 is formed flush with thefront wall 228. The crossing line between the front end face 248 a andthe side end face 247 c is formed as a tapered surface 248 c, therebyimproving the insertion property of the joint connector 225.

The upper end face of the front end 248 is formed flush with the upperend face 247 a of the side end 247. The upper end face 247 a is parallelto the lower face 227 a of the board 227. The upper face and the lowerface 227 a abut against the respective walls of the connector-fittingchamber 218, thereby positioning of the joint connector 225 in its upand down direction (i.e. a direction crossing the insertion direction ofthe connector at right angles).

With the construction of the guide rib 224 as described above, thepositioning of the joint connector 225 is carried out for the twodirections (left and right direction, and up and down direction) whichcross the front and rear direction at right angles, thereby restrictingthe electric contact 234-side of the female terminal 233, which ismounted in the joint connector 225, preventing an undesirableinterference between the terminals from occurring, and improving thereliability of the terminal connection.

The female terminal 233 is the same as a normal female terminal and isformed by stamping an electrically conductive plate and by bending. Thefemale terminal 233 is provided with a box-shaped electric contact 234on one side thereof and an electric wire-connecting part 235 on theopposite side thereof. Inside the electric contact 234, a resilientcontact piece 234 a is formed being bent and clips the tab terminal 243a, 244 a of the busbars 243, 244. The electric wire-connecting part 235includes a pair of crimp-contact pieces 235 a, 235 b situated in frontand rear, to which a core 241 a and insulating coating 241 b of theelectric wire 241 are crimp-contacted. The electric wire-connecting part235 may be a pair of pressure-welding pieces.

In the following, a joint box (i.e. an electric junction box) will beexplained, by which a joint connector never slips off from aconnector-fitting part of a joint connector block, the joint connectorcan be securely mounted, and a good workability of the mounting can beattained.

FIG. 21 illustrates a preferred embodiment of an electric junction boxaccording to the present invention.

The joint box 310 (electric junction box) includes a joint connectorblock 312 and joint connectors 325. The joint connector block 312includes a casing 313 made of insulating resin, a plurality of busbars323 having at least one terminal, which busbar are inserted into thecasing 313 from the bottom, and a cover 322 made of insulating resin forpreventing each busbar 323 from coming off. Each joint connector 325,which is connected to electric wires 341, is inserted into the casing313 from the top. The joint connector 325, to which the electric wires341 is connected, is inserted from the top of the casing 313. A femaleterminal 333 is connected to a tab terminal 323 a of the busbar 323.

The joint box 310 according to the present invention includes: a casing313, which includes a connector-fitting part 317 having a plurality ofconnector-fitting chambers 318 on the upper side and a busbar-receivingpart 319 for receiving busbars 323 with a terminal on the lower side; ahousing 326 for receiving female terminals 333 to be connected to a tabterminal 323 a of the busbar 323; and joint connectors 325, 325′ (thejoint connector 325′ being shown in FIG. 23) which fit into theconnector-fitting part 317, wherein each projection (provisionallyengaging part) 318 c is formed on an inner surface of a correspondingside wall 314 a that constitutes the connector-fitting chambers 318, anda concave part for engaging with the projection 318 c is formed on anouter surface of the corresponding side wall 331 of the housing 326.After a plurality of the joint connectors 325, 325′ is provisionallyengaged, the joint connectors 325, 325′ is completely engaged by anengaging spacer (completely engaging member) 337, which includes aconnection part 338 and a pair of arms 339 that continues to both endsof the connecting part 338. The horizontal connecting part 338 is put tothe ends of the joint connectors 325, while the pair of the arms 339that continues to the connecting part 338 crossing it at right angles isengaged with an outer wall 314 of the casing 313.

With the construction described above, even when the electric wire 341connected to the female terminal 333 is abruptly pulled during assemblyof the joint connectors 325, 325′ into the connector-fitting chamber318, the joint connectors 325, 325′ are prevented from coming off fromthe connector-fitting chamber 318, thereby enabling one-by-oneassembling of a plurality of the joint connectors 325, 325′ without aninterruption. After all of the joint connectors 325, 325′ are assembled,the joint connectors 325, 325′ are completely engaged with the engagingspacer 337, thereby the joint connectors 325, 325′ are securely fixedand the reliability of the joint-connection can be maintained.

A concave part instead of the projection 318 c may be formed on theinner surface of both side walls 314 a of the connector-fitting chamber318, while a projection instead of the concave part 331 a may be formedon the outer surface of both side walls 331 of the housing 326. However,according to the preferred embodiment, in which the projection 318 c isformed on the inner surface of both side walls 314 a of theconnector-fitting chamber 318, and the concave part 331 a is formed onthe outer surface of both side walls 331 of the housing 326, themoldability of both side walls 314 a, which are thin walls forpartitioning the connector-fitting chamber 318, can be improved.

In the following, a primary constitutional part and its functionalaction of the joint box 10 will be explained in detail.

The casing 313, which constitutes a joint connector block 312, includesa connector-fitting part 317 in its upper half and a busbar-receivingpart 319 in its lower half. The connector-fitting part 317 includes aplurality of slot-shaped connector-fitting chambers 318 arranged in aline. Each connector-fitting chamber 318 is formed being partitioned byvertical partition walls 318 a with the same pitch in a frame surroundedby the walls situated in front and behind, and left and right. Thepartition wall 318 a and a rear wall 314 c are provided with a pluralityof ribs 318 b with the same pitch. A space for receiving a terminal isformed between the ribs 318 b. The projection length of each rib 318 bis small. Each partition wall 329 of the housing 326 of the jointconnector 325, 325′ is positioned corresponding to the corresponding rib318 b.

Each connector-fitting chamber 318 has an opening at the upper thereof.Narrow walls situated left and right are side walls 314 a situated leftand right facing each other of the casing 313. Wide walls situated infront and rear are a partition wall 318 a, front wall 314 b or rear wall314 c. An inner face of the side walls 314 a situated left and right isprovided with a projection 318 c for engaging with a concave part 331 aof the joint connector 325, 325′. The projection 318 c has a triangularshape in a cross section cut along the insertion direction of the jointconnector 325, 325′ and is positioned at the middle of the up and downdirection of the connector-fitting chamber 318.

The projection 318 c has an inclined surface (not shown) and an engagingsurface (not shown). The inclined surface is formed gradually projectingas advancing into the deep of the connector-fitting chamber 318, whilethe engaging surface is formed crossing the inner face at right angles.When the joint connector 325, 325′ is inserted into theconnector-fitting chamber 318, the side walls 331 situated left andright climb up the inclined surface so as to advance into the deep, thenthe side walls 331 situated left and right climb over the inclinedsurface and then, the concave part 331 a engages with the projection 318c, thereby fixing the joint connector 325, 325′ and preventing the jointconnector 325, 325′ from abruptly coming off from the connector-fittingchamber 318.

The projecting length of the projection 318 c is adjusted so that thefitting resistance does not become very large, thereby improving themounting property and maintenance of the joint connector 325, 325′. Thatis, the projecting length is adjusted so that the joint connector 325,325′ does not come off due to an abrupt pull by a wiring harness.

The joint connector 325, 325′ is a multi-polar outside connector forreceiving the female terminals 333 of sixteen poles. After the jointconnectors 325, 325′ are mounted, each joint connector 325, 325′ doesnot come off due to the friction resistance between the terminals 323 a,333. However, upon the mounting of the joint connector 325, 325′, if apull force to be applied to the electric wire 341 is larger than thefriction resistance between the terminals 323 a, 333, the jointconnectors 325, 325′ might come off. According to the present invention,in this respect, each joint connector 325, 325′ is securely preventedfrom coming off by an engaging force with the provisional engaging meansin addition to the friction resistance between the terminals 323 a, 333.

With the provisional engaging means as described above, each jointconnector 325, 325′ is prevented from being incompletely fit or halfwayfit, thereby improving the workability of mounting of each jointconnector 325, 325′ and the reliability of the mounting.

In the preferred embodiment described above, the projection 318 c isformed on the side walls 314 a situated both sides. Instead, theprojection 318 c may be formed on the one side wall 314 a, the partitionwall 318 a, the front wall 314 b or the rear wall 314 c. If theprojection 318 c is formed on both side walls 314 a, the positionstability of the joint connector 325, 325′ improves.

Both ends in front and rear of the casing 313 is integrally providedwith a bracket 320 having a hole for fixing. A bolt (not shown) passesthrough the hole 320 a, thereby the bracket 320 is fixed on a panel (notshown) of a vehicle body.

A frame 316 for receiving an arm 339 of the engaging spacer 337 isformed at a corner of an outer wall 314 and outside theconnector-fitting part 317 of the joint connector block 312.

The frame 316 has a rectangular cylindrical shape. In the cylinder,there is formed a projection 316 a for engaging with an engaging claw339 a that is formed on the end side of the arm 339. The projection 316a has a triangle shape in its cross section including an inclinedsurface and engaging surface situated in front and rear in the insertiondirection of the arm 339. The inclined surface is a slide surface. Thearm 339 is inserted into the cylinder with a weak insertion force,thereafter the engaging claw 339 a engages with the engaging surface ofthe projection 316, thereby the arm 319 is fixed.

As described above, the arm 339 of the spacer 337 is inserted into thecylinder of the frame 316, thereby the arm 339 is protected by the frame316 and preventing the arm 339 from abruptly coming off due to anexternal interference.

With a bottom wall 314 d shown in FIG. 22, the busbar-receiving part 319situated on the lower side is communicated to the connector-fitting part317 through the tab-insertion hole 315. The tab terminal 323 a of thebusbar 323 with at least one terminal penetrates through thetab-insertion hole 315 and projects into the connector-fitting chamber318. The projecting length of the tab terminal 323 a is formed a littlesmaller than the length of an electric contact 334 of the femaleterminal 333 shown in FIG. 23, so that the terminals 323 a and 333 areelectrically connected to each other.

The busbar 323 with terminal is formed by stamping an electricallyconductive plate and bending. The busbar 323 includes a band-shapedconnection part 323 b as its body and a plurality of tab terminals 323 aprojecting from the connection part 323 b crossing the connection part323 b at right angles. A plurality of the busbars 323 are partiallyconnected, thereby forming a joint circuit.

The cover 322 (see FIG. 21) is formed in a box-shape including framewalls 322 a and a bottom wall 322 b. The upper part of the cover 322 isopen. After each busbar 323 is mounted on the busbar-receiving part 319,the cover 322 is applied onto the busbar-receiving part 319 from thebottom, thereby preventing the busbars 323 from coming off. The cover322 and the casing 313 are fixed to each other by engaging a projectionand a concave part, for example, thereby the cover 322 is prevented fromcoming off from the casing 313.

The spacer 337 made of insulating resin has a rectangular shapeincluding the connection part 338 extending straightly in the horizontaldirection, a pair of arms 338 continuing to both ends of the connectionpart 338 crossing at right angles, and a vertical depending wall 340continuing to one side of the connection part 338 crossing at rightangles. A slit 340 a is formed at a crossing line between the arm 339and the vertical depending wall 340. The arm 339 can be bent. The backface of the connection part 338 is formed flat and put to the ends ofplurality of the joint connectors 325, 325′, thereby completely fixingthe joint connectors 325, 325′. The inner surface of the verticaldepending wall 340 is formed flat and put to the side wall 314 a at oneside of the casing 313. The vertical depending wall 340 is put to theside wall 314 a of the casing 313, thereby the spacer 337 is preventedfrom being deformed.

The inner surface at the end side of the arm 339 is provided with anengaging claw 339 a projecting inwardly. When the spacer 339 faces theside wall 314 a of the casing 313 and the spacer 339 is put to the sidewall 314 a of the casing 313, the arm 339 is inserted into the cylinderof the frame 316 and the engaging claw 339 a engages with the projection316 a in the cylinder, thereby fixing the spacer 337. Thus, theconnection part 338 is put to the ends of a plurality of the jointconnectors 325, 325′, so that plurality of the joint connectors 325,325′ are completely engaged as a whole, thereby securely fixing thejoint connectors 325, 325′.

As shown in FIG. 23, the joint connector 325′ (325) includes femaleterminals 333 to be connected to the tab terminal 323 a of the busbar323 and a plate-shaped housing 326. The joint connector 325′ and theelectric wires 341 to be connected to the female terminal 333 constitutea wiring harness.

The housing 326 made of insulating resin includes a flat board 327,partition walls 329 and front walls 328 standing up crossing at rightangles from the board 327. The rear wall and the upper wall facing theboard of the housing 326 are formed open. The width of the board 327 isadjusted corresponding to the width of the connector-fitting chamber 318of the casing 313 so as not to make a gap. A projection 329 a forpreventing the female terminal 333 from coming out is formed at themiddle of the partition wall 329. The projection length of theprojection 329 a is formed so as not to obstruct the insertion of thefemale terminal 333 which is inserted from the top.

A thin and long terminal-receiving part 330 is formed between theadjacent partition walls 329 of the housing 326 so as to receive thefemale terminal 333 form a direction indicated by an arrow in FIG. 23.The electric contact 334 of the received terminal 333 abuts against thefront wall 328 of the housing 326 so as not to come off in the forwarddirection, while the electric contact 334 abuts against the projection329 a so as not to come off in the backward direction. That is, thefemale terminal 333 received in the terminal-receiving part 330 does notcome off from the terminal-receiving part 330.

Insertion holes 328 a for inserting the tab terminals 323 a of thebusbar 323 are formed in the front walls 328 of the housing 326. Theinlet of the hole 328 a is formed on a tapered surface 328 b, therebyeach tab terminal 323 a is guided by the tapered surface 328 a so as tobe inserted into the electric contact 334 of the female terminal 333,and clipped by a resilient force of a resilient contact piece 334 a.

A concave part 331 a for engaging with the projection 318 c for theprovisional engagement of the connector-fitting chamber 318 is formed onthe side walls 331 situated at both sides left and right of the housing326. The concave part 331 a is formed in a notch-shape at the middle ofthe longitudinal direction of the side wall 331. The vertical surface onthe front side of the concave part 331 a is an engaging surface 331 bfor engaging with the projection 318 c.

In the preferred embodiment as described above, the concave part 331 bis formed on the side walls 331 situated at both sides. Instead, theconcave part 331 b may be formed on the side wall 331 at one side,partition wall 329 or board 327. If the concave part 331 b is formed onboth side walls 331, the position stability of the joint connector 325′improves.

The housings 326 that are inserted into a plurality of theconnector-fitting chambers 318 have the same shape with each other, andare cut and manufactured from a housing material 332, in which thehousings 326 are continued in a chain-shape, thereby reducing the costof the molds and molding and reducing the cost of the joint box 310.

The female terminal 333 is the same as a normal female terminal and isformed by stamping an electrically conductive plate and by bending. Thefemale terminal 333 is provided with a box-shaped electric contact 334on one side thereof and an electric wire-connecting part 335 on theopposite side thereof. Inside the electric contact 334, a resilientcontact piece 334 a is formed being bent and clips the tab terminal 323a of the busbars 323. The electric wire-connecting part 335 includes apair of crimp-contact pieces 335 a, 335 b situated in front and rear, towhich a core 341 a and insulating coating 341 b of the electric wire 341are crimp-contacted. The electric wire-connecting part 335 may be a pairof pressure-welding pieces.

INDUSTRIAL APPLICABILITY

According to the invention described in claim 1, each branch terminal ofthe longitudinal and lateral busbars is arranged in a matrix-shape andconnected to a wiring harness and so on, thereby enabling to easily meeta demand of a complicated and highly dense joint circuit form and ademand of a joint circuit form that varies depending on types of avehicle, increasing the degree of freedom in a circuit designing,enabling to easily respond to a change in the circuit, improvingflexibility for various types of a vehicle, and reducing the cost of ajoint connector block.

According to the invention described in claim 2, the slit groovepositions the longitudinal busbar, while the lateral slit positions thelateral busbar, thereby each longitudinal and lateral busbar isaccurately connected without a positional shift and improving thereliability of joint-connection.

According to the invention described in claim 3, since each branchterminal of the longitudinal and lateral busbars is accuratelypositioned in the concave groove, therefore the branch terminal isaccurately connected to a terminal in the outside connector in theconnector-fitting chamber without a positional shift, enabling to carryout the connecting process smoothly and securely, and improving thereliability of joint-connection.

According to the invention described in claim 4, each branch terminal ofthe longitudinal and lateral busbars can be densely arranged beingintermingled in a line in the connector-fitting chamber, therebyenabling to make the outside connector thin and to make thejoint-connection structure compact.

According to the invention described in claim 5, each branch terminal ofthe longitudinal and lateral busbars is insulated mutually by the rib inthe connector-fitting chamber, thereby preventing a short circuit andpreventing a damage due to an interference between the terminals uponassembling of the busbars, and improving the reliability ofjoint-connection.

According to the invention described in claim 6, the connecting part ofthe lateral busbar can be easily securely inserted into and connected tothe pair of the clip terminals of the longitudinal busbar, and theconnecting state of both busbars can be checked by visual observation,thereby improving the workability of the connection process andimproving the reliability of joint-connection.

According to the invention described in claim 7, the cover prevents eachbusbar from slipping off, thereby attaining no need to engage eachbusbar with the block body and making the structure of the block bodysimple, compact and low-cost.

According to the invention described in claim 8, the lateral busbar ispositioned with the groove of the cover, thereby preventing a positionalshift of the lateral busbar relative to the pair of the clip terminalsof the longitudinal busbar and preventing wear due to the vibration upontraveling of a vehicle. Further, the rib abuts against the longitudinalbusbar, thereby preventing the longitudinal busbar from having back-lashand preventing the longitudinal busbar from wearing against the lateralbusbar, and thereby improving the reliability of joint-connection.

According to the invention described in claim 9, the positioning of thelateral busbar is improved and the workability of mounting of the coveris improved.

According to the invention described in claim 10, a laterally linkedterminal is cut into a required shape so as to meet a demand of a jointcircuit which varies depending on types of a vehicle, thereby enablingto reduce the number of molds for molding busbars (stamping and bending)so as to reduce the cost.

According to the invention described in claim 11, it becomes possible tomeet a demand of a circuit of the outside wiring harness, said circuitincluding a part not to be connected. Further, the branch terminals ofthe longitudinal and lateral busbars can be highly intermingled, therebyenabling to easily meet a demand of a complicated joint circuit with alow cost.

1. A joint connector block comprising: a block body having a pluralityof connector-fitting chambers arranged in a line on one side of theblock body, for receiving connectors of at least one outside wiringharness, and a busbar-receiving part communicating with theconnector-fitting chambers on an opposite side of the block body; aplurality of longitudinal busbars, each of which includes at least onebranch terminal projecting in the connector-fitting chamber and at leastone pair of clip terminals situated on the side of the busbar-receivingpart; and a plurality of lateral busbars, each of which includes atleast one branch terminal projecting in the connector-fitting chamberand a connecting part to be connected to the pair of the clip terminalson the side of the busbar-receiving part, the lateral busbar beingconnected to at least two of said longitudinal busbars crossing thelongitudinal busbars at right angles; wherein said branch terminals ofsaid longitudinal busbars and said branch terminals of said lateralbusbars are arranged in a line in said connector-fitting chambers forconnecting with connectors of the at least one outside wiring harness.2. The joint connector block as claimed in claim 1, wherein the branchterminal of the longitudinal busbar is offset in a direction crossing atright angles from a connection part from which the pair of the clipterminals protrudes, while the branch terminal of the lateral busbar ison the same plane as that of the connection part of the lateral busbar.3. The joint connector block as claimed in claim 1, wherein a pluralityof ribs are projectingly formed on a partition wall of theconnector-fitting chamber, the rib insulating the branch terminals ofeach said longitudinal or lateral busbar from each other.
 4. The jointconnector block as claimed in claim 1, wherein each end of the pair ofthe clip terminals protrudes outward from the busbar-receiving part. 5.The joint connector block as claimed in claim 1, wherein a cover isfitted to the block body and each said longitudinal or lateral busbarabuts against the cover, thereby preventing each busbar from slippingout.
 6. The joint connector block as claimed in claim 1, wherein eachsaid longitudinal or lateral busbar is formed by cutting a laterallylinked terminal into a required shape.
 7. The joint connector blockaccording to claim 6, wherein an unnecessary pair of the clip terminalor branch terminal is cut off from the connecting part of thelongitudinal or lateral busbar, and/or the connecting part is cut into arequired length or cut at a required position.
 8. The joint connectorblock according to claim 1, wherein the busbar-receiving part includes:a plurality of slit grooves, each of which receives the longitudinalbusbar; and a plurality of lateral slits, each of which engages with theconnecting part of the lateral busbar, the lateral slit crossing theslit groove at right angles.
 9. The joint connector block as claimed inclaim 8, wherein the branch terminal of the longitudinal busbar isoffset in a direction crossing at right angles from a connection partfrom which the pair of the clip terminals protrudes, while the branchterminal of the lateral busbar is on the same plane as that of theconnection part of the lateral busbar.
 10. The joint connector block asclaimed in claim 8, wherein a plurality of ribs are projectingly formedon a partition wall of the connector-fitting chamber, the rib insulatingthe branch terminals of each said longitudinal or lateral busbar fromeach other.
 11. The joint connector block as claimed in claim 8, whereina cover is fitted to the block body and each said longitudinal orlateral busbar abuts against the cover, thereby preventing each busbarfrom slipping out.
 12. The joint connector block as claimed in claim 8,wherein each said longitudinal or lateral busbar is formed by cutting alaterally linked terminal into a required shape.
 13. A joint connectorblock comprising: a block body having a plurality of connector-fittingchambers arranged in a line on one side of the block body and abusbar-receiving part communicating with the connector-fitting chamberson an opposite side of the block body; a plurality of longitudinalbusbars, each of which includes at least one branch terminal projectingin the connector-fitting chamber and at least one pair of clip terminalssituated on the side of the busbar-receiving part; and a plurality oflateral busbars, each of which includes at least one branch terminalprojecting in the connector-fitting chamber and a connecting part to beconnected to the pair of the clip terminals on the side of thebusbar-receiving part, the lateral busbar being connected to thelongitudinal busbar crossing the longitudinal busbar at right angles;wherein the busbar-receiving part includes: a plurality of slit grooves,each of which receives the longitudinal busbar; and a plurality oflateral slits, each of which engages with the connecting part of thelateral busbar, the lateral slit crossing the slit groove at rightangles; and a concave groove is formed in a partition wall of theconnector-fitting chamber continuously from the lateral slit, the branchterminal of each said longitudinal or lateral busbar being insertedthrough the concave groove.
 14. The joint connector block as claimed inclaim 13, wherein the branch terminal of the longitudinal busbar isoffset in a direction crossing at right angles from a connection partfrom which the pair of the clip terminals protrudes, while the branchterminal of the lateral busbar is on the same plane as that of theconnection part of the lateral busbar.
 15. The joint connector block asclaimed in claim 13, wherein a plurality of ribs are projectingly formedon a partition wall of the connector-fitting chamber, the rib insulatingthe branch terminals of each said longitudinal or lateral busbar fromeach other.
 16. The joint connector block as claimed in claim 8, whereineach end of the pair of the clip terminals protrudes outward from thebusbar-receiving part.
 17. The joint connector block as claimed in claim13, wherein each end of the pair of the clip terminals protrudes outwardfrom the busbar-receiving part.
 18. The joint connector block as claimedin claim 13, wherein a cover is fitted to the block body and each saidlongitudinal or lateral busbar abuts against the cover, therebypreventing each busbar from slipping out.
 19. A joint connector block,comprising a block body having a plurality of connector-fitting chambersarranged in a line on one side of the block body and a busbar-receivingpart communicating with the connector-fitting chambers on an oppositeside of the block body; a plurality of longitudinal busbars, each ofwhich includes at least one branch terminal projecting in theconnector-fitting chamber and at least one pair of clip terminalssituated on the side of the busbar-receiving part; and a plurality oflateral busbars, each of which includes at least one branch terminalprojecting in the connector-fitting chamber and a connecting part to beconnected to the pair of the clip terminals on the side of thebusbar-receiving part, the lateral busbar being connected to thelongitudinal busbar crossing the longitudinal busbar at right angles;wherein a cover is fitted to the block body and each said longitudinalor lateral busbar abuts against the cover, thereby preventing eachbusbar from slipping out; and the cover includes: a plurality of ribsagainst each of which an end of each said pair of the clip terminalsabuts; and a plurality of grooves, each of which is formed between theribs, the connection part of the lateral busbar entering in said groove.20. The joint connector block according to claim 19, wherein said grooveis provided with an inclined shaped guide surface on the inlet side ofthe groove.